Rounding rules ignored by Price Sales Transaction API, but work fine in UI

Summary:

We are using one rounding rule for EUR. Through the application UI, it works as expected, but it is ignored by Price Sales Transaction.
We are unable to figure out which parameter for PST we are missing.

Content (please ensure you mask any confidential information):

Manage Rounding Rules:

Manage Rounding Rule Assignments:

This is the amount calculated through UI and is correct (40,31€):

However, the following payload:

 {

    "Header": [

        {

            "CalculatePricingChargesFlag": true,

            "CalculateTaxFlag": true,

            "HeaderId": 1,

            "TransactionOn": "2026-03-24",

            "PricingStrategyId": 300000016275112,

            "SellingLegalEntityId": 300000001996008,

            "SellingBusinessUnitId": 300000001884144,

            "PriceAsOf": "2026-03-24T12:31:09.407+00:00",

            "TransactionTypeCode": "ORA_SALES_ORDER"

        }

    ],

    "Line": [

        {

            "HeaderId": 1,

            "InventoryItemId": 100000013131573,

            "InventoryOrganizationId": 300000001900766,

            "LineCategoryCode": "ORDER",

            "LineId": 1001,

            "LineQuantityUOMCode": "m2",

            "LineQuantity": {

                "Value": 1.44,

                "UomCode": "m2"